Faster microscope imaging inside living cells

A NEW technique to combine two distinct microscope technologies can create sharper images of rapid processes inside a cell, say its inventors.

Scientists at the US National Institute of Biomedical Imaging and Bioengineering (NIBIB) developed the technique to apply High Resolution Optical Imaging (HROI) to improve Total Internal Reflection Fluorescence (TIRF) microscopy.

The rapid movements of Rab11 particles can be clearly imaged with the new instant TIRF-SIM microscope. Image courtesy Hari Shroff, US National Institute of Biomedical Imaging and Bioengineering

TIRF microscopy illuminates samples at an acute angle, so that light reflects back and only a thin section of the sample close to the coverslip is illuminated.

This eliminates much out-of-focus background light and creates very high contrast images.

However, conventional TIRF produces blurry images of small features within cells.

So-called super-resolution microscopy techniques have been able to improve TIRF resolution, but slow down the process so much that it has been impossible to generate sharp images of fast-moving objects.